Focusing device.



J. KIRBY, 1n.

FOCUSING DEVICE.

APPLICATION FILED AUG.29, 1918.

1,295,523, Patented Feb. 25, 1919.

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5'0 KIBBY, J'lR.., OF DAYTON, OHIO, ASSIGNOR T UNITED STATES HEADLIGHTCOMPANY, OF BUFFALO, NEW YORK, A CORPORATION OF NEW YORK.

To all whom it may concern:

Be it known that 1, JOHN KIRBY, Jr., a citizen of the United States,residing at Dayton, in the county of Montgomery and State f Ohio, haveinvented a certain new and useful Improvement in Focusing Devices, ofwhich the following is a specification.

My invention relates primarily to electric headlights and has for itspurpose to provide mechanism for adjusting the filament of anincandescent lamp to the focal point of a parabolic reflector, as setforth in my previous application, Serial Number 219,383, filed August12, 1918, and from which my present invention diflerentiates in certamparticulars not described, or claimed therein but which will be madeclear in this specification and pointed out in the claims at the endthereof.

In headlights of the type to which my invention is applicable it isessential that the center of illumination be located with accuracy inrespect of the focal point of the re flector and to this end myinvention consists in the novel construction and combination of partshereinafter more fully set forth and claimed.

The invention is illustrated in the accompanying drawings, whichconstitute a part of this specification and in which Figure 1 is' a sideview, partly in full and partly in section, of a portion of thereflectorwith the focusing device mounted thereon and showing the standwhich supports the rear end of the reflector, and Fig. 2 is a rear view,one half being shown in section through the line A-A of Fig. 1.

Like reference numerals indicate corresponding parts throughout thedrawings.

1 represents a portion of the reflector, the front end of which may bemounted upon any suitable slide or base, as 2, in the usual manner, notshown. A ring 3 is secured to the rear of the reflector, the apex ofwhich is cut away at4 leaving an opening corresponding to the innerdiameter of the said ring 3. At the bottom of and preferably integralwith the said ring 3 there is a laterally disposed arm or bracketextension 5 having a depending screw threaded member 6, which inconjunction with the standard 7 and nuts 8 and 9 constitute means bywhich the rear end of the reflector is adjustably supported upon thebase 2 as more fully described in my pre- "lous application, abovereferred to. The

Specification of Letters Patent.

liatented Feb. 25, 1919.

Application filed August 29, 1918. Serial No. 251,913.

free end of the bracket 5 is provided with an interiorly screw threadedboss 10 to receive a corresponding exteriorly screw threaded plug 11depending from a member 12, having a seat which forms the lower bearingfor a spherical element or ball 13, and which, when screwed to place,may be secured against displacement by a pin 14. The bearing member 12extends upwardly to, substantially, the center of the ball and isprovided with an exteriorly screw threaded portion 15 to receive acorresponding interiorly screw threaded portion 16 of a cap 17, the capbeing provided with a bearing portion 18 adapted to hold the ballagainst movement when the cap is screwed down tight and the ball therebyfirmly gripped between said upper and lower bearings which inconjunction with the ball constitutes what is commonly known as a balljoint. At the top of and in vertical line with the center of the ball13, and preferably integral therewith, there is an exteriorly screwthreaded stud 19, which engages an interiorly screw threaded lug or boss20 depending from a horizontally disposed hollow sleeve 21, and which isprevented from turning thereon by a pin 22. The sleeve 21 carries alongitudinally movable lamp socket holder 23 having a bore 24 throughwhich pass current con ducting wires, not shown, leading to the lampsocket 25 and conveying electric current to the lamp filament 26, in theusual manner, the focal point of the reflector being shown at The sleeve21 is provided with an outstanding lug 27, and secured to the rear orfree end of the socket holder 23 there is a collar 28 having anextension or arm 29 disposed opposite the said lug 27 the latter beingdrilled and tapped to receive a regulating screw- 30, the reduced shank,31, of which passes through a smooth bore in the extension 29, and tothe outer end of this shank there is secured a hand wheel 32, bywh-ichthe regulating screw may be turned and the socket holder therebymoved forward or backward according to the direction in'which said screwis turned. Interposed between the lug 27 and the extension 29, andsurrounding the regulating screw, there is a coiled spring 33, which isretained in place by bosses 34 and 35; the function of this 1 movementof the socket holder, otherwise liable to occur from jars and vibrationincident to a moving locomotive or other vehicle.

The plug 11 is provided with a receptacle 36, within which there islocated a coiled spring 37, having one end bearing against the bottom ofsaid receptacle and its opposite end bearing against the ball 13, asshown; the purpose of this spring being to w exert yielding pressure onthe ball, so that when the screw pressure ofthe cap is relievedsufficient to permit the ball to move freely in its bearings, the actionof the spring will press the ball against the bearing 15 portion 18, ofthe cap 17, with sufiicient force to require slight hand pressure tomove the ball, to which a steady movement is thereby contributed duringthe operation of setting the device.

Supplementary to the use of the cap 17 as a means of tightening the ballagainst undue movement, and to provide auxiliary means therefor, thebottom of the plug 11 is drilled and tapped to receive a set screw 38which passes through the center of the spring 37 and which is providedwith a finger piece 39, by which it can be turned to engage the ball insuch manner as to materially assist in holding the same secure againstundue displacement.

It is to be understood that when the parts are assembled, as shown inthe drawings, but little movement will be required to adjust thefilament to its proper relation to the reflector, and such movement maybe had by a slight turn of the cap 17 and the set screw 38, to relievethe screw pressure on the-ball 13 and leave the same free to be movedabout in spherical direction, forward and backward movement of thesocket holder being obtained, independently of such spherical movement,by turning the regulating screw 30. Then, when the filament is properlyadjusted, the ball is permanently gripped by turning the cap 17 and theset screw 38, as hereinbefore explained.

Having thus fully described the construction and operation of myinvention as embodying the best manner of carrying out 5 the same I donot wish to be understood as limiting the invention to focusingdevice's, nor to the specific details shown and described, as it isobvious that the same may be used for other purposes and that itsconstruction as herein detailed may be departed from in various wayswithout departing from the scope and spirit of the invention.

What I claim and desire to secure by Letters Patent is:

co 1. In a focusing device, a bracket carrying adjustable capconstituting a movable hearing for said ball and adapted to engage andco-act with said fixed bearing to exert and relieve pressure on saidball, in combination with a lamp socket holder and a,support 7 therefor,and regulative means for imparting to said socket holder longitudinalmove ment independently of said ball.

In a focusing device for headlights, the combination with a reflector ofa bracket and a support therefor, 21 fixed ball bearing carried bysaid'bracket, a ball located in said bearing, an adjustable capconstituting a movable bearing for said ball and adapted to engage andco-act with said fixed bearing to grip and release said ball, areceptacle having communication with said fixed bearing, a springlocated in said receptacle adapted to exert yielding pressure on saidball, a lamp socket holder and a tubular support therefor carried bysaid ball, a lug protruding from said tubular support and having athreaded perforation therethrough, an arm fixed to and extending fromsaid socket holder provided with a smooth perforation therethrough, anda regulating screw operative through said perforations whereby saidsocket holder may be moved forward and backward independently ofmovement of said ball. 5

3. In a focusing device for headlights, the combination with a reflectorof a bracket and a support therefor, a fixed ball bearing carried bysaid bracket, a ball located in said bearing, an adjustable capconstituting a movable bearing for said ball and adapted to engage andco-act with said fixed bearing to grip and release said ball,areceptacle having communication with said fixed bearing, a springlocated in said receptacle adapted to exert yielding pressure on saidball, a lamp socket holder and a tubular support therefor carried bysaid ball, a lug protruding from said tubular support and having athreaded perforation therethrough, an arm fixed to and extending fromsaid socket holder provided with a smooth perforation therethrough, aregulating screw operative through said perforations whereby said socketholder may be moved forward and backward independently of movement ofsaid ball, and a spring arranged to reduce tendency to undue movement ofsaid regulating screw.

4. Ina focusing device for headlights, the combination with a reflectorof a bracket and a support therefor, a fixed ball bearing carried bysaid bracket, a ball located in said bearing, an adjustable capconstituting a movable bearing for said ball and adapted to engage andco-act with said fixed bearing to grip and release said ball, areceptacle having communication with said fixed bearing, a springlocated in said receptacle adapted to exert yielding pressure on saidball, a lam socket holder and a tubular support therefor carried by said'ball, a lug protruding from said tubular support and having a threadedperforation therethrou'gh, an arm fixed to and extending from saidsocket holder provided with a smooth perforation therethrough, aregulating screw operative through said perforations whereby said socketholder may lw moved forward and backward indepent mly of movement 'ofsaid ball, and auxiliary means for securing said ball against movementin said bearings.

5. In a focusing device for headlights, the

combination with a reflector of a bracket and a support therefor, afixed ball bearing carried by said bracket, a ball'located in saidbearing, an adjustable cap constituting a movable bearing for said balland adapted to engage and co-act with said fixed bearing to grip andrelease said ball, a receptacle having communication with said fixedbearing, a spring located in said receptacle adapted to exert yieldingpressure on said ball, a lamp socket holder and a tubular supporttherefor carried by said'ball, a lug protruding from said tubularsupport and having a threaded perforation therethrough, an arm fixedto'and extending from said socket holder provided with asmoothperforation therethrough, a regulating screw. operative throughsaid perforations whereby lating screw, and auxiliary means for securmgsa1d ball against movement 1n sa1d bear- 1ngs.

6. In a device of the character described, the combination of a singlespherical element and a supporting bearing therefor having a dependingmember, a bracket support for said member, a chamber formedin saidmemberand extending through said supporting bearing, a spring located insaid chamber, and. a movable block adapted to impinge the surface ofsaid element and to cooperate with said spring to steady the movement ofsaid element.

In testimony whereof, I 'aflix my signature in the presence of twowitnesses this 21st day of August, 1918.

JOHN KIRBY, J R.

Witnesses:

NORMAN J oNEs, LOUISE S'roLz.

